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Porosia
''Porosia'' is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. Described in 1942, it used to be a monotypic genus with the sole species '' P. bigibbosa''. However a second species, '' P. paracarinata'', was discovered in 2015. Morphology The original 1942 description of ''Porosia'' corresponds to the type species '' P. bigibbosa''. The description was expanded in 2015 to fit both species. The organism consists of a pyriform, laterally compressed test with a rounded posterior end, two large invaginated pores situated on each lateral compression, both of which connected by internal tubes in ''Certesella''. Small lateral pores are seen anterior to the large ones. Lateral keels, present in '' P. paracarinata'' but absent in '' P. bigibbosa'', surround a third of the posterior lateral margins. The test itself is composed of euglyphid shell plates embedded in a disorganized cement. The test's aperture or "pseudostome" is surrounded with a lip made of orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porosia Bigibbosa
''Porosia'' is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. Described in 1942, it used to be a monotypic genus with the sole species ''Porosia bigibbosa, P. bigibbosa''. However a second species, ''Porosia paracarinata, P. paracarinata'', was discovered in 2015. Morphology The original 1942 description of ''Porosia'' corresponds to the type species ''Porosia bigibbosa, P. bigibbosa''. The description was expanded in 2015 to fit both species. The organism consists of a pyriform, laterally compressed test (biology), test with a rounded posterior end, two large invaginated pores situated on each lateral compression, both of which connected by internal tubes in ''Certesella''. Small lateral pores are seen anterior to the large ones. Lateral keels, present in ''Porosia paracarinata, P. paracarinata'' but absent in ''Porosia bigibbosa, P. bigibbosa'', surround a third of the posterior lateral margins. The test itself is composed of euglyphid shell plate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porosia Paracarinata
''Porosia'' is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. Described in 1942, it used to be a monotypic genus with the sole species '' P. bigibbosa''. However a second species, '' P. paracarinata'', was discovered in 2015. Morphology The original 1942 description of ''Porosia'' corresponds to the type species '' P. bigibbosa''. The description was expanded in 2015 to fit both species. The organism consists of a pyriform, laterally compressed test with a rounded posterior end, two large invaginated pores situated on each lateral compression, both of which connected by internal tubes in ''Certesella''. Small lateral pores are seen anterior to the large ones. Lateral keels, present in '' P. paracarinata'' but absent in '' P. bigibbosa'', surround a third of the posterior lateral margins. The test itself is composed of euglyphid shell plates embedded in a disorganized cement. The test's aperture or "pseudostome" is surrounded with a lip made of o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyalospheniidae
Hyalospheniidae is a group of testate amoebae and the sole family of the infraorder Hyalospheniformes. Hyalospheniid testate amoebae are considered important bioindicators, which is why they are frequently used for environmental monitoring and their fossils are studied to investigate the paleoecology. Phylogeny The following cladogram illustrates the evolutionary relationships between all hyalospheniid genera found through phylogenetic analysis, with the exception of '' Porosia'', a genus excluded from the analysis that appears to be closely related to ''Certesella'' and is therefore placed next to it in the cladogram. Classificaton The current taxonomy of the family recognizes 14 genera: * Infraorder Hyalospheniformes Lahr et al. 2019 ** Family Hyalospheniidae Schulze 1877 emend. Kosakyan & Lara 2014 *** ''Alabasta'' Duckert et al., 2018 *** ''Alocodera'' Jung, 1942 *** ''Apodera'' Loeblich & Tappan, 1961 *** ''Certesella'' Loeblich & Tappan, 1961 *** '' Cornutheca'' Kosakyan et a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcellinid
Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially enclosed in a simple test (shell). Arcellinid testate amoebae are commonly found in soils, leaf litter, peat bogs and near/in fresh water. They use their pseudopodia, a temporary cell extension, for moving and taking in food. Like most amoebae, they are generally believed to reproduce asexually via binary fission. However a recent review suggests that sexual recombination may be the rule rather than the exception in amoeboid protists in general, including the Arcellinid testate amoebae. Test or shell Simple tests are made by secretion (autogenous tests), agglutination of foreign material (xenogenous tests), or sometimes a combination of both. Past environmental changes can be determined by analysing the composition of fossil tests, incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testate Amoebae
Testate amoebae (formerly thecamoebians, Testacea or Thecamoeba) are a polyphyletic group of unicellular amoeboid protists, which differ from naked amoebae in the presence of a test that partially encloses the cell, with an aperture from which the pseudopodia emerge, that provides the amoeba with shelter from predators and environmental conditions. The test of some species is produced entirely by the amoeba and may be organic, siliceous or calcareous depending on the species (autogenic tests), whereas in other cases the test is made up of particles of sediment collected by the amoeba which are then agglutinated together by secretions from within the cell (xenogenic tests). A few taxa (Hyalosphenidae) can build either type, depending on the circumstances and availability of foreign material. The assemblage referred to as "testate amoebae" is actually composed of several, unrelated groups of organisms. However, some features they all share that have been used to group them together ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Certesella
Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially enclosed in a simple test (shell). Arcellinid testate amoebae are commonly found in soils, leaf litter, peat bogs and near/in fresh water. They use their pseudopodia, a temporary cell extension, for moving and taking in food. Like most amoebae, they are generally believed to reproduce asexually via binary fission. However a recent review suggests that sexual recombination may be the rule rather than the exception in amoeboid protists in general, including the Arcellinid testate amoebae. Test or shell Simple tests are made by secretion (autogenous tests), agglutination of foreign material (xenogenous tests), or sometimes a combination of both. Past environmental changes can be determined by analysing the composition of fossil tests, includ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Test (biology)
In biology, a test is the hard shell of some spherical marine animals and protists, notably sea urchins and microorganisms such as testate foraminiferans, radiolarians, and testate amoebae. The term is also applied to the covering of scale insects. The related Latin term testa is used for the hard seed coat of plant seeds. Etymology The anatomical term "test" derives from the Latin ''testa'' (which means a rounded bowl, amphora or bottle). Structure The test is a skeletal structure, made of hard material such as calcium carbonate, silica, chitin or composite materials. As such, it allows the protection of the internal organs and the attachment of soft flesh. In sea urchins The test of sea urchins is made of calcium carbonate, strengthened by a framework of calcite monocrystals, in a characteristic "stereomic" structure. These two ingredients provide sea urchins with a great solidity and a moderate weight, as well as the capacity to regenerate the mesh from the cuticle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euglyphid
The euglyphids are a prominent group of filose amoebae that produce shells or tests from siliceous scales, plates, and sometimes spines. These elements are created within the cell and then assembled on its surface in a more or less regular arrangement, giving the test a textured appearance. There is a single opening for the long slender pseudopods, which capture food and pull the cell across the substrate. Euglyphids are common in soils, marshes, and other organic-rich environments, feeding on tiny organisms such as bacteria. The test is generally 30-100 μm in length, although the cell only occupies part of this space. During reproduction a second shell is formed opposite the opening, so both daughter cells remain protected. Different genera and species are distinguished primarily by the form of the test. ''Euglypha'' and ''Trinema'' are the most common. The euglyphids are traditionally grouped with other amoebae. However, genetic studies instead place them with var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphagnum
''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, peat moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store water, since both living and dead plants can hold large quantities of water inside their cells; plants may hold 16 to 26 times as much water as their dry weight, depending on the species.Bold, H. C. 1967. Morphology of Plants. second ed. Harper and Row, New York. p. 225-229. The empty cells help retain water in drier conditions. As sphagnum moss grows, it can slowly spread into drier conditions, forming larger mires, both raised bogs and blanket bogs. Thus, sphagnum can influence the composition of such habitats, with some describing sphagnum as 'habitat manipulators'. These peat accumulations then provide habitat for a wide array of peatland plants, including sedges and Calcifuges, ericaceous shrubs, as well as orchids and carnivorous plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hornworts. Mosses typically form dense green clumps or mats, often in damp or shady locations. The individual plants are usually composed of simple leaves that are generally only one cell thick, attached to a stem that may be branched or unbranched and has only a limited role in conducting water and nutrients. Although some species have conducting tissues, these are generally poorly developed and structurally different from similar tissue found in vascular plants. Mosses do not have seeds and after fertilisation develop sporophytes with unbranched stalks topped with single capsules containing spores. They are typically tall, though some species are much larger. ''Dawsonia'', the tallest moss in the world, can grow to in height. There are a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former term specifically to displaced soil. Soil consists of a solid phase of minerals and organic matter (the soil matrix), as well as a porous phase that holds gases (the soil atmosphere) and water (the soil solution). Accordingly, soil is a three-state system of solids, liquids, and gases. Soil is a product of several factors: the influence of climate, relief (elevation, orientation, and slope of terrain), organisms, and the soil's parent materials (original minerals) interacting over time. It continually undergoes development by way of numerous physical, chemical and biological processes, which include weathering with associated erosion. Given its complexity and strong internal connectedness, soil ecologists regard soil as an ecosystem. Most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amoebozoa Genera
Amoebozoa is a major taxonomic group containing about 2,400 described species of amoeboid protists, often possessing blunt, fingerlike, lobose pseudopods and tubular mitochondrial cristae. In traditional and currently no longer supported classification schemes, Amoebozoa is ranked as a phylum within either the kingdom Protista or the kingdom Protozoa. In the classification favored by the International Society of Protistologists, it is retained as an unranked "supergroup" within Eukaryota. Molecular genetic analysis supports Amoebozoa as a monophyletic clade. Modern studies of eukaryotic phylogenetic trees identify it as the sister group to Opisthokonta, another major clade which contains both fungi and animals as well as several other clades comprising some 300 species of unicellular eukaryotes. Amoebozoa and Opisthokonta are sometimes grouped together in a high-level taxon, variously named Unikonta, Amorphea or Opimoda. Amoebozoa includes many of the best-known amoeboid organis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
